1. Field of the Invention
This invention relates to dry wall finishing tools and particularly to tools adapted to be used to make a smooth finished corner junction between intersecting sheetrock or drywall panels.
2. Prior Art
In the installation of drywall or sheetrock panels, the panels are normally nailed or glued in side-by-side relationship to make a flat wall and are placed in end-to-end engagement at right angles to join at corners of a room. The edges of the panels are normally somewhat beveled and tape and a drywall compound, generally referred to as "mud" are used to fill the crevasse formed by the end-to-end engagement of the panels.
The tapes used are usually made of paper or a fiberglass mesh and one side is coated with mud before the tape is applied to the corner junction with the mud beneath the tape.
The most common method of smoothing the tape and smoothing the mud into a corner junction is believed to be with use of wide blade putty knives. However, some V-shaped tools have been proposed and used in the past. The tools with which I am familiar are all made of metal and have V-shaped wings with flat surfaces. In using such tools it is generally necessary to have the tape, with mud applied thereto, rolled with a special roller to press the mud deep into the corner and to spread the mud. A smaller head is most effective in creating a proper corner but often will leave ridges at the outer edges of the tape where the mud is pressed out by the tool. If a larger tool is used it often rides into the corner, engages the tapered edges and extends upwardly and outwardly away from the wall so that mud collected therebeneath will harden into a ridge.
It has also been found that as these known tools slide along a corner tape they cause the mud to plow ahead of the tools. This raises and buckles the tape. As a tool passes, it wipes the tape smooth again but a great deal of work is required to move the tool. The drag developed is also partially the result of the metal, usually stainless steel, from which the tool is constructed.